To be competitive you must want to win. It’s essential to have the will to win but controversially not at any cost.
So how can you teach the desire to win?
Human motivation is an expansive area of study. We do things for a variety of reasons. Hunger, self preservation and competitiveness to name a few.
At a young age most people are externally motivated. For example they want to win a prize. As you get older you become more internally motivated. For example you want to feel accomplished by achievement of something important.
A coach can use these motivational tools to their advantage to encourage a desire to win.
If there are not many opportunities to win a prize a coach can set up a system of awards (like badges) or even simple things like a treat or prize. Controversial, I know. I’m not a big proponent of ‘everyone gets a prize’ but it does have its place, and you’d be surprised how winning a sweetie can motivate a whole squad!
Even something as simple as a list can be very motivating. Club records, club milestones or a club record board.
Another list that motivates swimmers are national rankings and later in a swim career, world rankings. I remember as a young swimmer trying desperately to make it onto the National age group rankings in the SwimCanada magazine that came out each month published by Nick Thierry. Although these type of things are all online now but ‘back in the day’ this was a great tool. I wrote a blog specifically about rankings: Swim magazine

A magazine with worn out pages!
Winning a race is often more than just wanting a prize. So a good coach needs to find out the right buttons to push.
A pre-race chat is extremely valuable. Something about a race can always be found out which will help install a desire to win. A ‘start sheet’ or ‘psych sheet’ (or also called a ‘heat sheet’) is a great tool to help find that desire to win. For example; maybe moving up from eighth place to seventh, or beating a certain person, or knowing that being close to another swimmer will ensure a personal best time. All of these things, and more, can be coaxed out of the start sheet.

A new race is a blank canvas
In addition to the start sheet and good tool at a coaches disposal is video. With video commonly available, sometimes a will to win can be shown to a swimmer (especially between heats and finals) by showing how they can improve. For example if your swimmer was beat on turns this can be shown easily with video. Then some time spent on correcting these things prior to the race, in warm up, will ensure great motivation to race better in that specific aspect. What can be shown to the swimmer is the impact the poor turn made at the end of the race. So logically, if the turns are fixed, the race should come down to a close finish. That then should be a ‘surprise’ to their competition and a swimmer with this knowledge can win.
Swimmers who are young will from time to time cheat to win. This is an opportunity to chastise them for being unsportsmanlike. The true competitive person is honourable and can take defeat as a motivation to learn from mistakes. An essential part of coaching must be to respect the definition of ‘sport’. Coaches are critical in this area.
Good luck! And as I like to say to swimmers; may the gods of starts and turns be good to you!